--- /dev/null
+/**
+ * APM X-Gene PCIe Driver
+ *
+ * Copyright (c) 2014 Applied Micro Circuits Corporation.
+ *
+ * Author: Tanmay Inamdar <tinamdar@apm.com>.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/clk-private.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/memblock.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define PCIECORE_CTLANDSTATUS 0x50
+#define PIM1_1L 0x80
+#define IBAR2 0x98
+#define IR2MSK 0x9c
+#define PIM2_1L 0xa0
+#define IBAR3L 0xb4
+#define IR3MSKL 0xbc
+#define PIM3_1L 0xc4
+#define OMR1BARL 0x100
+#define OMR2BARL 0x118
+#define OMR3BARL 0x130
+#define CFGBARL 0x154
+#define CFGBARH 0x158
+#define CFGCTL 0x15c
+#define RTDID 0x160
+#define BRIDGE_CFG_0 0x2000
+#define BRIDGE_CFG_4 0x2010
+#define BRIDGE_STATUS_0 0x2600
+
+#define LINK_UP_MASK 0x00000100
+#define AXI_EP_CFG_ACCESS 0x10000
+#define EN_COHERENCY 0xF0000000
+#define EN_REG 0x00000001
+#define OB_LO_IO 0x00000002
+#define XGENE_PCIE_VENDORID 0x10E8
+#define XGENE_PCIE_DEVICEID 0xE004
+#define SZ_1T (SZ_1G*1024ULL)
+#define PIPE_PHY_RATE_RD(src) ((0xc000 & (u32)(src)) >> 0xe)
+
+struct xgene_pcie_port {
+ struct device_node *node;
+ struct device *dev;
+ struct clk *clk;
+ void __iomem *csr_base;
+ void __iomem *cfg_base;
+ unsigned long cfg_addr;
+ bool link_up;
+};
+
+static inline u32 pcie_bar_low_val(u32 addr, u32 flags)
+{
+ return (addr & PCI_BASE_ADDRESS_MEM_MASK) | flags;
+}
+
+/* PCIe Configuration Out/In */
+static inline void xgene_pcie_cfg_out32(void __iomem *addr, int offset, u32 val)
+{
+ writel(val, addr + offset);
+}
+
+static inline void xgene_pcie_cfg_out16(void __iomem *addr, int offset, u16 val)
+{
+ u32 val32 = readl(addr + (offset & ~0x3));
+
+ switch (offset & 0x3) {
+ case 2:
+ val32 &= ~0xFFFF0000;
+ val32 |= (u32)val << 16;
+ break;
+ case 0:
+ default:
+ val32 &= ~0xFFFF;
+ val32 |= val;
+ break;
+ }
+ writel(val32, addr + (offset & ~0x3));
+}
+
+static inline void xgene_pcie_cfg_out8(void __iomem *addr, int offset, u8 val)
+{
+ u32 val32 = readl(addr + (offset & ~0x3));
+
+ switch (offset & 0x3) {
+ case 0:
+ val32 &= ~0xFF;
+ val32 |= val;
+ break;
+ case 1:
+ val32 &= ~0xFF00;
+ val32 |= (u32)val << 8;
+ break;
+ case 2:
+ val32 &= ~0xFF0000;
+ val32 |= (u32)val << 16;
+ break;
+ case 3:
+ default:
+ val32 &= ~0xFF000000;
+ val32 |= (u32)val << 24;
+ break;
+ }
+ writel(val32, addr + (offset & ~0x3));
+}
+
+static inline void xgene_pcie_cfg_in32(void __iomem *addr, int offset, u32 *val)
+{
+ *val = readl(addr + offset);
+}
+
+static inline void xgene_pcie_cfg_in16(void __iomem *addr, int offset, u32 *val)
+{
+ *val = readl(addr + (offset & ~0x3));
+
+ switch (offset & 0x3) {
+ case 2:
+ *val >>= 16;
+ break;
+ }
+
+ *val &= 0xFFFF;
+}
+
+static inline void xgene_pcie_cfg_in8(void __iomem *addr, int offset, u32 *val)
+{
+ *val = readl(addr + (offset & ~0x3));
+
+ switch (offset & 0x3) {
+ case 3:
+ *val = *val >> 24;
+ break;
+ case 2:
+ *val = *val >> 16;
+ break;
+ case 1:
+ *val = *val >> 8;
+ break;
+ }
+ *val &= 0xFF;
+}
+
+/*
+ * When the address bit [17:16] is 2'b01, the Configuration access will be
+ * treated as Type 1 and it will be forwarded to external PCIe device.
+ */
+static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
+{
+ struct xgene_pcie_port *port = bus->sysdata;
+
+ if (bus->number >= (bus->primary + 1))
+ return port->cfg_base + AXI_EP_CFG_ACCESS;
+
+ return port->cfg_base;
+}
+
+/*
+ * For Configuration request, RTDID register is used as Bus Number,
+ * Device Number and Function number of the header fields.
+ */
+static void xgene_pcie_set_rtdid_reg(struct pci_bus *bus, uint devfn)
+{
+ struct xgene_pcie_port *port = bus->sysdata;
+ unsigned int b, d, f;
+ u32 rtdid_val = 0;
+
+ b = bus->number;
+ d = PCI_SLOT(devfn);
+ f = PCI_FUNC(devfn);
+
+ if (!pci_is_root_bus(bus))
+ rtdid_val = (b << 8) | (d << 3) | f;
+
+ writel(rtdid_val, port->csr_base + RTDID);
+ /* read the register back to ensure flush */
+ readl(port->csr_base + RTDID);
+}
+
+/*
+ * X-Gene PCIe port uses BAR0-BAR1 of RC's configuration space as
+ * the translation from PCI bus to native BUS. Entire DDR region
+ * is mapped into PCIe space using these registers, so it can be
+ * reached by DMA from EP devices. The BAR0/1 of bridge should be
+ * hidden during enumeration to avoid the sizing and resource allocation
+ * by PCIe core.
+ */
+static bool xgene_pcie_hide_rc_bars(struct pci_bus *bus, int offset)
+{
+ if (pci_is_root_bus(bus) && ((offset == PCI_BASE_ADDRESS_0) ||
+ (offset == PCI_BASE_ADDRESS_1)))
+ return true;
+
+ return false;
+}
+
+static int xgene_pcie_read_config(struct pci_bus *bus, unsigned int devfn,
+ int offset, int len, u32 *val)
+{
+ struct xgene_pcie_port *port = bus->sysdata;
+ void __iomem *addr;
+
+ if ((pci_is_root_bus(bus) && devfn != 0) || !port->link_up)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ if (xgene_pcie_hide_rc_bars(bus, offset)) {
+ *val = 0;
+ return PCIBIOS_SUCCESSFUL;
+ }
+
+ xgene_pcie_set_rtdid_reg(bus, devfn);
+ addr = xgene_pcie_get_cfg_base(bus);
+ switch (len) {
+ case 1:
+ xgene_pcie_cfg_in8(addr, offset, val);
+ break;
+ case 2:
+ xgene_pcie_cfg_in16(addr, offset, val);
+ break;
+ default:
+ xgene_pcie_cfg_in32(addr, offset, val);
+ break;
+ }
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int xgene_pcie_write_config(struct pci_bus *bus, unsigned int devfn,
+ int offset, int len, u32 val)
+{
+ struct xgene_pcie_port *port = bus->sysdata;
+ void __iomem *addr;
+
+ if ((pci_is_root_bus(bus) && devfn != 0) || !port->link_up)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ if (xgene_pcie_hide_rc_bars(bus, offset))
+ return PCIBIOS_SUCCESSFUL;
+
+ xgene_pcie_set_rtdid_reg(bus, devfn);
+ addr = xgene_pcie_get_cfg_base(bus);
+ switch (len) {
+ case 1:
+ xgene_pcie_cfg_out8(addr, offset, (u8)val);
+ break;
+ case 2:
+ xgene_pcie_cfg_out16(addr, offset, (u16)val);
+ break;
+ default:
+ xgene_pcie_cfg_out32(addr, offset, val);
+ break;
+ }
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops xgene_pcie_ops = {
+ .read = xgene_pcie_read_config,
+ .write = xgene_pcie_write_config
+};
+
+static u64 xgene_pcie_set_ib_mask(void __iomem *csr_base, u32 addr,
+ u32 flags, u64 size)
+{
+ u64 mask = (~(size - 1) & PCI_BASE_ADDRESS_MEM_MASK) | flags;
+ u32 val32 = 0;
+ u32 val;
+
+ val32 = readl(csr_base + addr);
+ val = (val32 & 0x0000ffff) | (lower_32_bits(mask) << 16);
+ writel(val, csr_base + addr);
+
+ val32 = readl(csr_base + addr + 0x04);
+ val = (val32 & 0xffff0000) | (lower_32_bits(mask) >> 16);
+ writel(val, csr_base + addr + 0x04);
+
+ val32 = readl(csr_base + addr + 0x04);
+ val = (val32 & 0x0000ffff) | (upper_32_bits(mask) << 16);
+ writel(val, csr_base + addr + 0x04);
+
+ val32 = readl(csr_base + addr + 0x08);
+ val = (val32 & 0xffff0000) | (upper_32_bits(mask) >> 16);
+ writel(val, csr_base + addr + 0x08);
+
+ return mask;
+}
+
+static void xgene_pcie_linkup(struct xgene_pcie_port *port,
+ u32 *lanes, u32 *speed)
+{
+ void __iomem *csr_base = port->csr_base;
+ u32 val32;
+
+ port->link_up = false;
+ val32 = readl(csr_base + PCIECORE_CTLANDSTATUS);
+ if (val32 & LINK_UP_MASK) {
+ port->link_up = true;
+ *speed = PIPE_PHY_RATE_RD(val32);
+ val32 = readl(csr_base + BRIDGE_STATUS_0);
+ *lanes = val32 >> 26;
+ }
+}
+
+static int xgene_pcie_init_port(struct xgene_pcie_port *port)
+{
+ int rc;
+
+ port->clk = clk_get(port->dev, NULL);
+ if (IS_ERR(port->clk)) {
+ dev_err(port->dev, "clock not available\n");
+ return -ENODEV;
+ }
+
+ rc = clk_prepare_enable(port->clk);
+ if (rc) {
+ dev_err(port->dev, "clock enable failed\n");
+ return rc;
+ }
+
+ return 0;
+}
+
+static int xgene_pcie_map_reg(struct xgene_pcie_port *port,
+ struct platform_device *pdev)
+{
+ struct resource *res;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr");
+ port->csr_base = devm_ioremap_resource(port->dev, res);
+ if (IS_ERR(port->csr_base))
+ return PTR_ERR(port->csr_base);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+ port->cfg_base = devm_ioremap_resource(port->dev, res);
+ if (IS_ERR(port->cfg_base))
+ return PTR_ERR(port->cfg_base);
+ port->cfg_addr = res->start;
+
+ return 0;
+}
+
+static void xgene_pcie_setup_ob_reg(struct xgene_pcie_port *port,
+ struct resource *res, u32 offset,
+ u64 cpu_addr, u64 pci_addr)
+{
+ void __iomem *base = port->csr_base + offset;
+ resource_size_t size = resource_size(res);
+ u64 restype = resource_type(res);
+ u64 mask = 0;
+ u32 min_size;
+ u32 flag = EN_REG;
+
+ if (restype == IORESOURCE_MEM) {
+ min_size = SZ_128M;
+ } else {
+ min_size = 128;
+ flag |= OB_LO_IO;
+ }
+
+ if (size >= min_size)
+ mask = ~(size - 1) | flag;
+ else
+ dev_warn(port->dev, "res size 0x%llx less than minimum 0x%x\n",
+ (u64)size, min_size);
+
+ writel(lower_32_bits(cpu_addr), base);
+ writel(upper_32_bits(cpu_addr), base + 0x04);
+ writel(lower_32_bits(mask), base + 0x08);
+ writel(upper_32_bits(mask), base + 0x0c);
+ writel(lower_32_bits(pci_addr), base + 0x10);
+ writel(upper_32_bits(pci_addr), base + 0x14);
+}
+
+static void xgene_pcie_setup_cfg_reg(void __iomem *csr_base, u64 addr)
+{
+ writel(lower_32_bits(addr), csr_base + CFGBARL);
+ writel(upper_32_bits(addr), csr_base + CFGBARH);
+ writel(EN_REG, csr_base + CFGCTL);
+}
+
+static int xgene_pcie_map_ranges(struct xgene_pcie_port *port,
+ struct list_head *res,
+ resource_size_t io_base)
+{
+ struct pci_host_bridge_window *window;
+ struct device *dev = port->dev;
+ int ret;
+
+ list_for_each_entry(window, res, list) {
+ struct resource *res = window->res;
+ u64 restype = resource_type(res);
+
+ dev_dbg(port->dev, "%pR\n", res);
+
+ switch (restype) {
+ case IORESOURCE_IO:
+ xgene_pcie_setup_ob_reg(port, res, OMR3BARL, io_base,
+ res->start - window->offset);
+ ret = pci_remap_iospace(res, io_base);
+ if (ret < 0)
+ return ret;
+ break;
+ case IORESOURCE_MEM:
+ xgene_pcie_setup_ob_reg(port, res, OMR1BARL, res->start,
+ res->start - window->offset);
+ break;
+ case IORESOURCE_BUS:
+ break;
+ default:
+ dev_err(dev, "invalid resource %pR\n", res);
+ return -EINVAL;
+ }
+ }
+ xgene_pcie_setup_cfg_reg(port->csr_base, port->cfg_addr);
+
+ return 0;
+}
+
+static void xgene_pcie_setup_pims(void *addr, u64 pim, u64 size)
+{
+ writel(lower_32_bits(pim), addr);
+ writel(upper_32_bits(pim) | EN_COHERENCY, addr + 0x04);
+ writel(lower_32_bits(size), addr + 0x10);
+ writel(upper_32_bits(size), addr + 0x14);
+}
+
+/*
+ * X-Gene PCIe support maximum 3 inbound memory regions
+ * This function helps to select a region based on size of region
+ */
+static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
+{
+ if ((size > 4) && (size < SZ_16M) && !(*ib_reg_mask & (1 << 1))) {
+ *ib_reg_mask |= (1 << 1);
+ return 1;
+ }
+
+ if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) {
+ *ib_reg_mask |= (1 << 0);
+ return 0;
+ }
+
+ if ((size > SZ_1M) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 2))) {
+ *ib_reg_mask |= (1 << 2);
+ return 2;
+ }
+
+ return -EINVAL;
+}
+
+static void xgene_pcie_setup_ib_reg(struct xgene_pcie_port *port,
+ struct of_pci_range *range, u8 *ib_reg_mask)
+{
+ void __iomem *csr_base = port->csr_base;
+ void __iomem *cfg_base = port->cfg_base;
+ void *bar_addr;
+ void *pim_addr;
+ u64 cpu_addr = range->cpu_addr;
+ u64 pci_addr = range->pci_addr;
+ u64 size = range->size;
+ u64 mask = ~(size - 1) | EN_REG;
+ u32 flags = PCI_BASE_ADDRESS_MEM_TYPE_64;
+ u32 bar_low;
+ int region;
+
+ region = xgene_pcie_select_ib_reg(ib_reg_mask, range->size);
+ if (region < 0) {
+ dev_warn(port->dev, "invalid pcie dma-range config\n");
+ return;
+ }
+
+ if (range->flags & IORESOURCE_PREFETCH)
+ flags |= PCI_BASE_ADDRESS_MEM_PREFETCH;
+
+ bar_low = pcie_bar_low_val((u32)cpu_addr, flags);
+ switch (region) {
+ case 0:
+ xgene_pcie_set_ib_mask(csr_base, BRIDGE_CFG_4, flags, size);
+ bar_addr = cfg_base + PCI_BASE_ADDRESS_0;
+ writel(bar_low, bar_addr);
+ writel(upper_32_bits(cpu_addr), bar_addr + 0x4);
+ pim_addr = csr_base + PIM1_1L;
+ break;
+ case 1:
+ bar_addr = csr_base + IBAR2;
+ writel(bar_low, bar_addr);
+ writel(lower_32_bits(mask), csr_base + IR2MSK);
+ pim_addr = csr_base + PIM2_1L;
+ break;
+ case 2:
+ bar_addr = csr_base + IBAR3L;
+ writel(bar_low, bar_addr);
+ writel(upper_32_bits(cpu_addr), bar_addr + 0x4);
+ writel(lower_32_bits(mask), csr_base + IR3MSKL);
+ writel(upper_32_bits(mask), csr_base + IR3MSKL + 0x4);
+ pim_addr = csr_base + PIM3_1L;
+ break;
+ }
+
+ xgene_pcie_setup_pims(pim_addr, pci_addr, ~(size - 1));
+}
+
+static int pci_dma_range_parser_init(struct of_pci_range_parser *parser,
+ struct device_node *node)
+{
+ const int na = 3, ns = 2;
+ int rlen;
+
+ parser->node = node;
+ parser->pna = of_n_addr_cells(node);
+ parser->np = parser->pna + na + ns;
+
+ parser->range = of_get_property(node, "dma-ranges", &rlen);
+ if (!parser->range)
+ return -ENOENT;
+ parser->end = parser->range + rlen / sizeof(__be32);
+
+ return 0;
+}
+
+static int xgene_pcie_parse_map_dma_ranges(struct xgene_pcie_port *port)
+{
+ struct device_node *np = port->node;
+ struct of_pci_range range;
+ struct of_pci_range_parser parser;
+ struct device *dev = port->dev;
+ u8 ib_reg_mask = 0;
+
+ if (pci_dma_range_parser_init(&parser, np)) {
+ dev_err(dev, "missing dma-ranges property\n");
+ return -EINVAL;
+ }
+
+ /* Get the dma-ranges from DT */
+ for_each_of_pci_range(&parser, &range) {
+ u64 end = range.cpu_addr + range.size - 1;
+
+ dev_dbg(port->dev, "0x%08x 0x%016llx..0x%016llx -> 0x%016llx\n",
+ range.flags, range.cpu_addr, end, range.pci_addr);
+ xgene_pcie_setup_ib_reg(port, &range, &ib_reg_mask);
+ }
+ return 0;
+}
+
+/* clear BAR configuration which was done by firmware */
+static void xgene_pcie_clear_config(struct xgene_pcie_port *port)
+{
+ int i;
+
+ for (i = PIM1_1L; i <= CFGCTL; i += 4)
+ writel(0x0, port->csr_base + i);
+}
+
+static int xgene_pcie_setup(struct xgene_pcie_port *port,
+ struct list_head *res,
+ resource_size_t io_base)
+{
+ u32 val, lanes = 0, speed = 0;
+ int ret;
+
+ xgene_pcie_clear_config(port);
+
+ /* setup the vendor and device IDs correctly */
+ val = (XGENE_PCIE_DEVICEID << 16) | XGENE_PCIE_VENDORID;
+ writel(val, port->csr_base + BRIDGE_CFG_0);
+
+ ret = xgene_pcie_map_ranges(port, res, io_base);
+ if (ret)
+ return ret;
+
+ ret = xgene_pcie_parse_map_dma_ranges(port);
+ if (ret)
+ return ret;
+
+ xgene_pcie_linkup(port, &lanes, &speed);
+ if (!port->link_up)
+ dev_info(port->dev, "(rc) link down\n");
+ else
+ dev_info(port->dev, "(rc) x%d gen-%d link up\n",
+ lanes, speed + 1);
+ return 0;
+}
+
+static int xgene_pcie_probe_bridge(struct platform_device *pdev)
+{
+ struct device_node *dn = pdev->dev.of_node;
+ struct xgene_pcie_port *port;
+ resource_size_t iobase = 0;
+ struct pci_bus *bus;
+ int ret;
+ LIST_HEAD(res);
+
+ port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
+ if (!port)
+ return -ENOMEM;
+ port->node = of_node_get(pdev->dev.of_node);
+ port->dev = &pdev->dev;
+
+ ret = xgene_pcie_map_reg(port, pdev);
+ if (ret)
+ return ret;
+
+ ret = xgene_pcie_init_port(port);
+ if (ret)
+ return ret;
+
+ ret = of_pci_get_host_bridge_resources(dn, 0, 0xff, &res, &iobase);
+ if (ret)
+ return ret;
+
+ ret = xgene_pcie_setup(port, &res, iobase);
+ if (ret)
+ return ret;
+
+ bus = pci_scan_root_bus(&pdev->dev, 0, &xgene_pcie_ops, port, &res);
+ if (!bus)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, port);
+ return 0;
+}
+
+static const struct of_device_id xgene_pcie_match_table[] = {
+ {.compatible = "apm,xgene-pcie",},
+ {},
+};
+
+static struct platform_driver xgene_pcie_driver = {
+ .driver = {
+ .name = "xgene-pcie",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(xgene_pcie_match_table),
+ },
+ .probe = xgene_pcie_probe_bridge,
+};
+module_platform_driver(xgene_pcie_driver);
+
+MODULE_AUTHOR("Tanmay Inamdar <tinamdar@apm.com>");
+MODULE_DESCRIPTION("APM X-Gene PCIe driver");
+MODULE_LICENSE("GPL v2");
projects / cascardo / linux.git / commitdiff